If you pressed all switches and you didn't get all the lights, sadly you need to reset the game... (like I did)
Apparently old save game files somehow fail to activate the switches in the first and second level.
You can reset progress by settings in the game, I tried a lot to change some values in the save file to keep my previous save file, but I ended up only with errors.
I did the game again, and right now I am confused if I got the ending or not. (I still can't open the chest in the spawn room)
Add me on discord ˞˞#3320 (copy the entire username, it has a special symbol) and I'll be glad to help as much as I know!